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ENVIRONMENTAL CHANGE AND THE AGRO-PASTORALIST LIVELIHOOD IN THE ANDES OF PERU
This dissertation research focuses on a high elevation Andean social-ecological system. It examines system linkages between climate, grazing pasture (wetlands), and agro-pastoralist livelihood strategies in an indigenous peasant community. Working within the conceptual framework of complex systems dynamics and sustainable livelihoods analysis, methods and concepts are synthesized from the disciplines of climatology, hydrology, remote sensing and political ecology, and results contribute to the transdisciplinary literature on vulnerability analysis within the context of environmental change.
In the Andes of southern Peru livelihoods are based on agro-pastoralist activities that rely on access to natural resources in the puna ecosystem. The majority of pastoralists in the study region are indigenous Quechua who in the higher elevations raise herds predominantly of alpaca and sheep. This region in Peru has the highest density of alpacas and is a national leader in the production of fiber. The people in the District of Nuñoa are extremely proud of their alpaca herding heritage and have recently declared the district to be the “World capital and patrimony of the Suri alpaca”. Alpaca are therefore both economically and culturally important. Together with other members in the camelidae family (llama, vicuña, and guanaco), alpaca are well suited to the high elevation puna ecosystem. Wetlands in the puna, known as bofedales, have hydrological and biological characteristics that make them a vital resource to the pastoralist livelihood.
Climatic and environmental perturbations may be more pronounced in mountain regions and the affects to local water balance, ecosystems, and humans may be more profound. The sensitivity, adaptive capacity, and hence vulnerability of individuals, groups, and livelihoods to perturbations is a complex function of social, political, and environmental factors. This research uses a hierarchy of spatial scales to understand climate variability in the region as well as spatial and temporal changes in the natural resource base. A case study of an agro-patoralist community allows for the characterization of two disturbance regimes (climate and land use and management) and the linkages between components in the herding system and climate system. The results indicate that there is periodicity in the regional hydroclimatology but a deterioration of the resource base in the watershed. Economic and political factors may be contributing to the overuse of natural pastures which increases the future vulnerability of alpaca herders to environmental change in the Nuñoa watershed
Nutrient cycling in Patagonian ecosystems
The knowledge on nutrient cycling in Patagonian ecosystems of Argentina is scarce. However, studies not directly focused on nutrient cycling provide relevant information about the mechanisms of nutrient conservation in the climatically different ecosystems of the region. Here, we identified indicators of litter decomposition and soil N mineralization rates of some representative species of the dominant plant functional groups along the wide precipitation gradient of Patagonia. Senescent leaves and litter of forest trees have higher C concentration and C/N ratio and lower N concentration than steppe shrubs. Within the tree life form, evergreen species have higher C/N ratio than deciduous species. Differences in N concentration between green and senescent leaves suggest a higher N use efficiency in forest trees than in steppe shrubs. Within the steppe, grasses have higher nutrient use efficiency than shrubs due to their higher C and much lower N, P and K content in senescent leaves and litter. Thus, we hypothesize the occurrence of (i) a gradient from nutrient-conserving ecosystems in wetter sites (Andean-Patagonian forest) to relatively nutrient-rich (low nutrient use efficient) ecosystems in drier sites (Patagonian steppe), and (ii) differences in nutrient conservation mechanisms among different functional groups: in the Andean-Patagonian forests N conservation and N use efficiency is greater in evergreens than in deciduous woody species and in conifers than in broad-leaf species, whereas in the Patagonian steppe, grasses have higher nutrient resorption than shrubs. Likely as a consequence of these differences in litter quality, potential N mineralization is greater in deciduous than in evergreen Patagonian forests. Within the steppe, N inineralization seems to depend on grass and shrub cover, which in turn is regulated by disturbance, largely grazing. Since nutrient conservation in vegetation, specially N, is associated to the rates of litter decomposition and soil N mineralization, the confirmation of these patterns would allow to predict ecosystem resilience and resistance to nutrient losses, and contribute to understand and predict the response of the different Patagonian species or functional groups to interannual climatic variability and natural or anthropogenic disturbances. There is a special need for further research on P cycling, nutrient allocation in vegetation, and field measurements of litter decomposition and N mineralization
A Formacao De Educadores Ambientais No Programa Cultivando Agua Boa Da Itaipu Binacional: A Participacao Como Um Elemento Desencadeador Da Governança Ambiental Comunitária
The present study shares data and information from the experience of Training Environmental Educators FEA of the Cultivando gua Boa CAB Program of Itaipu Binacional Based on participatory methodologies FEA seeks to stimulate reflection and collective action valuing local knowledge in building more sustainable communities FEA carries out the federal government s proposal synthesized in the Environmental Educator Training Program PROFEA whose creators are the Ministry of the Environment and the Ministry of Education This article presents the research results related to the processes of participation in the training of environmental educators and their contribution to the achievement of community environmental governance The adopted approach was qualitative and as methodological procedures bibliographic documentary and field research were used this was carried out based on observations and interview
Rapid Determination of Diuretics in Human Urine by Gas Chromatography – Mass Spectrometry Following Microwave Assisted Derivatization
This work presents a GC–MS–MS–MS method for the direct determination of clenbuterol in human urine. The method
3 comprises a pretreatment procedure and the instrumental analysis of the derivatives performed by GC–MS (ion trap) with
3 electron impact ionization. The GC–MS analysis allows isolation and characterization of specific fragments from the
1 original (MS ) molecular structure, and in particular, those fragments originating from the precursor ion cluster (m/z5335–
2 337) characteristic of clenbuterol. The MS product fragment m/z5300 is in turn used as a further precursor fragment
3 4 giving rise to a MS spectrum specific for clenbuterol. MS fragmentation spectra were also investigated. However, further
3 4 fragmentation of MS product ions does not lead to functional MS spectra nor to any significant increase in the
3 signal-to-noise ratio. The sensitivity limit of the MS technique is lower than 0.2 mg/ l, with a linear range between 0.5 and 5
mg/ l, thus matching the basic requirements for antidoping analysis according to the guidelines of the International Olympic
Committee. Due to its overall analytical performance, the method is presently being evaluated as a confirmation protocol to
be followed to detect illicit clenbuterol administration to the athletes, and compared with reference GC–MS and
GC–MS–MS techniques
The use of cytochrome P450 inhibitors in sport. A new generation of doping masking agents?
The activity of the CYP450 enzymes responsible for the phase I metabolism of most of the compounds included in the World Anti-Doping Agency (WADA) list of prohibited substances and methods could be strongly modified by the combined administration of other drugs such as, for example, the antidepressant, the antifungal and the H2 receptor antagonist agents. These compounds act as inhibitors of the CYP450 isoforms and it has been demonstrated that their co-administration with a drug that is also a CYP450 substrate may lead to a substantial alteration of the latter drug bioavailability, metabolism and excretion kinetics. In sports some classes of non-banned drugs, and primarily among them antidepressants, antifungals and the H2 receptor antagonists are extensively used, according to the information available on the doping control forms. Athletes may intentionally combine the CYP450 inhibitors with doping agents to modify in urine the time window of detection of the selected marker(s) of drug abuse, especially in those cases where the parent drugs are extensively metabolized
High levels of osteopontin associated with polymorphisms in its gene are a risk factor for development of autoimmunity/lymphoproliferation
The autoimmune/lymphoproliferative syndrome (ALPS) displays defective function of Fas, autoimmunities, lymphadenopathy/splenomegaly, and expansion of CD4/CD8 double-negative (DN) T cells. Dianzani autoimmune/lymphoproliferative disease (DALD) is an ALPS variant lacking DN cells. Both forms have been ascribed to inherited mutations hitting the Fas system but other factors may be involved. A pilot cDNA array analysis on a DALD patient detected overexpression of the cytokine osteopontin (OPN). This observation was confirmed by enzyme-linked immunosorbent assay (ELISA) detection of higher OPN serum levels in DALD patients (n = 25) than in controls (n = 50). Analysis of the OPN cDNA identified 4 polymorphisms forming 3 haplotypes (A, B, and C). Their overall distribution and genotypic combinations were different in patients (N = 26) and controls (N = 158) (P <.01). Subjects carrying haplotype B and/or C had an 8-fold higher risk of developing DALD than haplotype A homozygotes. Several data suggest that these haplotypes influence OPN levels: (1) in DALD families, high levels cosegregated with haplotype B or C; (2) in healthy controls, haplotype B or C carriers displayed higher levels than haplotype A homozygotes; and (3) in AB and AC heterozygotes, mRNA for haplotype B or C was more abundant than that for haplotype A. In vitro, exogenous OPN decreased activation-induced T-cell death, which suggests that high OPN levels are involved in the apoptosis defect
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